Operation Ice Bridge scientists and crew completed 21 successful flights over West Antarctica and returned home in time for Thanksgiving. Still flights over the icy continent continue. Scientists with another field campaign — Investigating the Cryospheric Evolution of the Central Antarctic Plate, or simply ICECAP — are making ongoing airborne investigations over East Antarctica.

Where have they flown and what have they observed? ICECAP’s University of Texas researcher Duncan Young provided some updates from the field:

Dec. 8, 2009

Right now we are preparing to begin our shift from McMurdo to Australia’s Casey Station via the joint French-Italian base on top of the ice sheet, Concordia, after completing our ICECAP flights out of McMurdo today with Flight 16, right down the maw of Byrd Glacier. Tomorrow we will use our survey plane to move people and cargo to Concordia, surveying all the way, and then return to McMurdo. On Wednesday we will move the rest of our people using our aircraft all the way to Casey from McMurdo. It is a complex multinational ballet, where the timing of weather at locations over 1,250 miles (2,012 kilometers) apart is critical. Then we will begin our ICECAP/Ice Bridge operations out of Casey Station with our Australian colleagues.

Dec. 22, 2009

Using an upgraded DC-3, we have completed five flights, each about seven hours long out of Casey Station, in addition to the 20 flights we completed out of McMurdo Station. Three of these Casey based flights have flown over 2,330 miles (3,750 kilometers) of ICESat tracks, over the rapidly lowering Totten and Denman Glaciers.

Denman Glacier; Credit: Jamin Greenbaum, University of Texas at Austin

Today we are conducting an ambitious 10-hour flight to finish off our Casey work for this season. We will be flying to Concordia Station in the center of the ice sheet, picking up fuel and base GPS data we have been gathering over the past ten days to help improve our aircraft positions, and thus the surface elevations we have been measuring.

Then we will fly along a ‘tie-line’ to connect several transects we flew last season to the Dome C ice core. By tracking ice layers in the radar data, we have a chance to find where some of the oldest ice in Antarctica might lie, perhaps more than a million years old. This old ice would contain greenhouse gasses from the past, leading to a better understanding of climate change if it is drilled. The aircraft will then return to Casey station along our last targeted ICESat line along Totten Glacier.

After this flight, we plan to move to Dumount d’Urville Station in time for a French Christmas dinner — if the katabatic winds there allow it …

SANTIAGO, Chile — For the first time in more than 40 days, the nose of the NASA DC-8 pointed north on Nov. 23 after taking off from Punta Arenas airport. We have completed our Antarctic survey flights and are heading back home to Palmdale, Calif. Before we start climbing to cruising altitude we fly at 300 feet above the Strait of Magellan just outside Punta Arenas to collect atmospheric chemistry data. After two passes over the strait, we head north towards Santiago and enjoy the spectacular view of the Patagonian Ice Fields and the Torres del Paine from 35,000 feet.

The Patagonian ice fields seen from 35,000 feet during the DC-8 flight from Punta Arenas to Santiago, Chile on Nov. 23. Photo by Michael Studinger.

Over the past five weeks, the Ice Bridge teams have collected a landmark data set over Antarctica. We had originally planned to fly 17 missions but actually accomplished 21. We have flown more than 155,000 kilometers or almost 100,000 miles. This is almost four times around the world in 40 days.

During this time, we collected high-precision measurements of the ice surface elevation of many glaciers and ice shelves in Antarctica. We have also mapped the thickness of the glacier ice and snow cover, have measured the freeboards and snow thicknesses of the sea ice in the Weddell and Ross seas, and have collected gravity measurements that will allow us to estimate how deep the water is beneath the floating glacier tongues.

We have collected an enormous amount of data and are keen to analyze the data together with our colleagues when we are back in our labs. From the analysis of this data we will gain a much more detailed understanding of how the glaciers, ice sheets, and sea ice respond to changes in the climate system.

A project of this size is only possible with the support of many people. We could not have done this without the help and support of our Chilean friends and colleagues in Punta Arenas and Valdivia, the airport and hotel staff, and the many NASA and university people back home who have worked long hours to make this project happen. We thank the National Science Foundation for giving us access to their forecasts. And we appreciate the help and assistance of the forecaster at the British Rothera Base (thanks Tony). For planning our flights, we also acknowledge our use of and dependence on the UCAR/NCAR NSF-supported Antarctic Mesoscale Prediction System. We had terrific aircraft crews both in the air and on the ground as well as excellent science teams.

We all had a great time in Punta Arenas and are looking forward to come back next year for another Ice Bridge campaign over Antarctica.

Map shows all the flight lines flown during the Operation Ice Bridge 2009 Antarctic campaign. Created by Michael Studinger.

PUNTA ARENAS, Chile – After flying for several hours over a windswept Southern Ocean on Tuesday, Oct. 27, the mission director announces that we will be slowly descending towards Antarctica’s Pine Island Glacier. Just below are the Hudson Mountains, a small group of extinct volcanoes poking through the ice.

As we approach our survey area, John Sonntag with NASA’s Wallops Flight Facility and I watch the navigation display and admire the pilots’ precision as they steer the giant NASA DC-8 aircraft to the start of our first survey line.

We are here to measure the glacier’s ice surface with lasers, its bottom with radar, and estimate the depth of the water below it with an instrument that measures the gravity pull from above the glacier.

All systems are functioning well and we are excited about the data coming in. The computer screen mounted on the University of Kansas’ radar rack is a popular in-flight gathering spot since it provides a real-time view of the radar data that allows us to “see” the bottom of the glacier while we fly over it.

The structures we see are quite amazing and we toss around ideas about what this tells us about how the glacier is responding to warming temperatures. Science can be so much fun! After criss-crossing Pine Island Glacier several times, it’s time to head home to Punta Arenas.

A heavily crevassed area of Pine Island Glacier. Shows you how very difficult it would be to travel and work on the surface of this glacier. Data are best collected from aircraft flying over the glacier or from space.

The calving front of Pine Island Glacier. This is the end of the glacier where pieces of ice break apart from the floating glacier and become icebergs.

Flying at low elevation over the edge of the floating part of Pine Island Glacier. Winds have blown away the sea ice resulting in an area with open water called a polynya. The goal of this flight is to estimate the thickness of the water layer beneath the floating ice shelf from gravity data.

The Hudson Mountains near the edge of Pine Island Glacier are a small group of extinct volcanoes that poke through the ice and make for spectacular scenery.

PUNTA ARENAS, Chile – The weather forecast for our survey area yesterday, Nov. 16, over the Larsen C Ice Shelf predicted excellent conditions. Given the difficult weather situation over the past couple of days, this was a welcome change. After carefully studying satellite images and computer models and talking to the meteorologist at the Punta Arenas airport, we decided to fly NASA’s DC-8 over Antarctica again.

The flight took us through an almost complete tour of the Antarctic cryosphere. We followed the flow of ice from the interior all the way to the ocean where it ends up as icebergs and eventually melts. We began our tour by flying over small ice caps on the Antarctic Peninsula. The snow and ice that forms these ice caps eventually flows downhill through steep valleys that are occupied by glaciers or ice streams.

Glaciers flowing down steep valleys transport ice from the interior of Antarctica to the Larsen Ice Shelf near the coast.

At one point during the flight I took the seat in the cockpit behind our two pilots to get a better view of the spectacular scenery. We descended into a steep valley that was filled with ice flowing into the remnants of the former Larsen B Ice Shelf that broke apart a few years ago. The ice that’s flowing down through the valleys is pushing the ice in the ice shelves away and eventually huge chunks of ice break off and form icebergs. On the ice shelf the ice goes afloat and forms huge flat surfaces that seem to be endless. Beneath the ice is ocean water. We are here to study how the warm ocean water melts the ice shelf from beneath.

Small caps of stagnant ice cover the summits while the ice in the valley is moving relatively fast towards the coast.

Our next survey line takes us all the way to the edge of the ice shelf where we can see several of these gigantic icebergs floating in the far distance surrounded by sea ice and pockets of open water. After crisscrossing the part of the Larsen C Ice Shelf that is still intact, we head back up to the crest of the Antarctic Peninsula and repeat our mini-tour through the Antarctic cryosphere on a different survey line.

Every time I look out of the window and soak in the spectacular scenery I see an incredibly beautiful but fragile landscape.

We fly over the flat and mostly featureless Larsen Ice Shelf. You can see the steep mountains and glaciers in the background.

We complete our tour of the Antarctic cryosphere at the edge of the Larsen C Ice Shelf where we reach open water and sea ice.

A last-minute change in flight plans made for another great science flight on Nov. 4. Initial plans were to make a high-altitude flight, according to program director Jim Yungel of NASA’s Wallops Flight Facility. But a forecaster in the Punta Arenas airport weather office advised crew of the potential forweather to interfere with the high-altitude measurements for themission’s LVIS instrument.

With a new flight plan in place, NASA’s DC-8 took off just a few minutes after the scheduled 11 a.m. departure time. The new plan called for low-altitude flights over the Antarctic Peninsula.

“The forecaster was completely correct,” Yungel wrote to colleagues after the flight. “We flew into sunny conditions with occasional very light high cirrus over flight lines, resulting in an outstanding data set over the Larsen Ice Shelf and many impressive glaciers.”

Instruments that collect data at lower altitudes, including the Airborne Topographic Mapper, had a successful 11.3-hour flight.

“Much of this flight surveyed a grid over the Larsen C Ice Shelf,” Yungel wrote. “Later in the flight we surveyed several significant glaciers in the central Peninsula area, including the Atlee, Flask, Crane, Hektoria, and Drygalski glaciers. It was a splendid day for flying glaciers!”

Despite the busy flight, Yungel managed to capture these images of the landscape from the aircraft window …

PUNTA ARENAS, Chile — Using the first potentially clear day on the Antarctic Peninsula since we began flights in mid-October, we decided to fly on to targets there on Saturday, Oct. 31.

The DC-8 flight path took us over ice elevation lines surveyed by the ATM laser instrument in October 2008. The path included tracks over the Fleming Glacier, one to the George V ice shelf and a parallel one over Palmer Land, plus a single pass down Crane Glacier. The purpose of these flights will be to study the glacier response to the collapse of the adjacent ice shelves. There was also a long grounding line flown around the inside of the Larson-C Ice Shelf. This was a challenging flight, with large elevation changes.

This map of our actual flight lines (in red) shows that at the most southern point or our flight plan we turned early to get out of the clouds.

About three and a half hours into the flight we flew the survey line down the Fleming Glacier followed by a descent over the Clifford Glacier. We had a beautiful run down Clifford glacier, which was about our steepest descent in the mission. We then headed north over the southern edge of the Larsen-C shelf.

Eight hours into the flight we descended over Crane Glacier into Exasperation Inlet, which is next to Cape Disappointment. The DC-8 pilots say we have a little extra time, so we are going to do a run up Atlee Glacier.

One of the scientists onboard came by with the observation that the remnant of Larsen-B in Carr Inlet was showing signs of breaking loose. This does appear to be the one part of the continent where climate change is actually visible, particularly in the northern ice shelves and glaciers. The removal of the buttressing effect of the Larsen-B has led to a speedup of the surrounding glaciers. We repeated Atlee Glacier, then overflew Palmer Station. With that we climbed up in altitude and headed back to Punta Arenas.

Although we lost the southern end of our flight lines due to clouds, we got all of our northern track. We also took 300 kilometers of track along the grounding line of the Larsen C, covering most of the shelf.

This is my last flight report from Antarctica. I’m rotating out and William Krabill of NASA Wallops Flight Facility will continue as Ice Bridge project scientist for the remainder of our Antarctica 2009 mission.

A nunatak sticking through cloud deck at the southern end of our traverse.

The foot of Crane Glacier, with glacier ice mixed with sea ice to the left, and the glacier to the right. If you look at the rock wall, there is a suggestion of the former height of the glacier and adjacent Larsen B ice shelf. The glacier surface height drop of about 100 meters has been confirmed by repeated laser observations.

From: Jill Hummels, Public Information Officer, University of Kansas School of Engineering

PUNTA ARENAS, Chile, Oct. 21 — Every flight in NASA’s Operation Ice Bridge mission begins and ends with a briefing. Today’s pilot Dick Ewers calls the disparate group to order and starts the morning with a roll call of the flight manifest. Every person on the flight must be accounted for with either a self-announced “Here!” or another passenger providing an accounting of their whereabouts as “on the plane.” Today’s total: 31.

The project scientist Seelye Martin then gives an overview of the day’s science objective, which instruments will be onboard that day, and which will play the lead role.

The flight crew provides a brief review of issues that need monitoring by all passengers and crew. At the top of the list: making sure lavatory faucets aren’t left running and ensuring everyone knows that “equipment and hot food have priority in the aisles.” The navigator announces some of the parameters for the day’s flight, such as altitude and duration. Other crew members reiterate safety awareness and the day’s schedule. “On the plane by 9. Doors close at 9:30. In the air by 10.”

Before taking off, all people on board must be on communication headsets. “Mission” (the flight crew) performs an audible check of all research instrument teams on board, and a representative from each team provides a status update.

Once airborne, researchers can choose to take off the headsets, but they are the best tool for communicating changing needs, problems, wishes, hopes and dreams with flight crew and the mission’s project science. Discussions, though not constant, are frequent.

About an hour into the flight, Mission announces impending pitch and roll maneuvers needed to calibrate some of the instruments.

Throughout the flight, everyone is free to move about the cabin, mingle, take pictures and talk shop.

Several instrument stations are outfitted with touch-screen monitors that provide real-time data, including satellite weather images, “webcams” of what’s directly in front of the plane and below it (below), and a Google Earth application that maps the current location of the DC-8.

Near the end of today’s roundtrip flight, the headsets are back on and everyone is back in their seats. Mission calls out each research team for a quick review of the day’s highlights, and any special landing procedures needed for data acquisition or instrument calibration.

On the ground, researchers quickly gather their personal belongings and any necessary portable equipment and haul it to the cramped mission offices at the airport. Within a half hour of the plane’s doors swinging open, all flight crew and researchers gather for a post-flight briefing on the day’s mission.

The day ends with a quick review of the next flight mission and schedule: “Briefing at 7. Power on at 7:30. Doors open by 8. Doors close by 8:30. In the air by 9.”